Sen. Bernie Sanders (I-Vt.) has made tackling climate change a key issue in his 2020 presidential campaign, but a video that resurfaced Tuesday shows that the independent was on top of the problem decades before it became a national focus.

A CNN reporter tweeted out a clip from a 1989 C-SPAN interview in which Sanders — who at the time was mayor of Burlington, Vermont — criticized the media for not reporting on climate change.

“We face, as all people know, an ecological crisis at this time — whether it’s acid rain or the destruction of the ozone layer, the greenhouse effect,” Sanders said on Feb. 3, 1989.

“One would think that the CBSs and the NBCs of the world would be doing prime-time specials on these programs, having different scientists talking about the issues, involving people in understanding what’s going on in terms of our planet,” he continued. “They don’t.”

Sanders suggested that the reason major television stations weren’t reporting on climate change was that they wouldn’t make money off the programming.

“I would say that we’re not going to bring about serious political change in this country until we deal with the media, which more and more is being swallowed up by large conglomerates,” he added.

Watch the full interview below:

In his campaign announcement last month, Sanders highlighted climate change as a focus of his campaign along with “Medicare-for-all” and free college tuition. He also promised his own version of a “green new deal.”

Watch the video below:

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In the old interview, Sanders talked about a lot of the same messages as in his current campaign promises, such as raising the minimum wage. At the time, Sanders was convinced that the United States needs a major third political party to address the issues.

Although he’s still a registered independent, Sanders said he would run under the Democratic ticket, just as he did in 2016. However, his self-identity as a “democratic socialist” and his willingness to bring climate change to the forefront of the political discussion shows that the presidential hopeful hasn’t changed his stance on many fundamental issues in over 30 years.